In this video, we show you how to unlock the Trek Domane+ eBike to achieve speeds greater than 25 km/h. By installing a tuning chip on the TQ-HPR50 motor, you can bypass the factory speed limits. This process will be very similar for other eBikes utilizing the same TQ motor. Below is a comprehensive, step-by-step guide to installing the chip yourself.
Step-by-Step PearTune Installation Guide
Phase 1: Accessing the Motor
- Prep the Bike: Flip the bike upside down so you can easily access and remove the motor.
- Remove the Bash Guard and Crank Arm: Remove the two Allen key bolts holding the bash guard (you don’t need to remove the chainring). Next, remove the screws on either side of the crank arm to take it off.
- Remove the Bash Cover: Carefully lift the guard up and clear the large bolt, being mindful not to damage the molded plastic around the lugs.
- Drop the Motor: Use two 6mm Allen keys to remove the motor bolts. Twist the front of the motor up and pull it back to lift it out of the frame. Locate the small speed sensor plug.
Phase 2: Removing the Charge Port and Battery
- Remove the Charge Port: Undo the three T8 Torx screws holding the charge port. Before pulling it out completely, locate the battery connector right on top of it. Push the clip down towards the charge port and pull the plug out. Now you can safely remove the charge port.
- Slide the Battery Out: Locate the pull string on the battery. Hold onto it so the battery doesn’t fall, and remove the Allen key holding the battery in at the bottom, followed by the 5mm Allen key at the very top near the fork. Slide the battery up and out of the frame.
Phase 3: Threading the Tuning Cable
- Remove the Top Tube Display: Undo the T10 Torx screw on the top tube and pop the display out.
- Route the Cable: Tape the lower plugs of the PearTune chip’s long cable to a small metal guide wire. Feed the wire from the display hole down the frame towards the motor area.
Phase 4: Lower Connections and Reassembly
- Connect to the Speed Sensor: Unplug the factory speed sensor from the motor. Plug the PearTune chip into the speed sensor (line up the logos), and plug the other end back into the motor.
- Reinstall the Battery & Charge Port: Carefully slide the battery back in and tighten the top and bottom bolts. Put the charge port back in (ensuring no cables are pinched) and secure the cover. Reconnect the battery plug, lining up the keyed side until you hear an audible click.
- Reinstall the Motor & Covers: Put the motor back in by going front-first and rotating it back into the frame. Jiggle it to line up the screw holes and reinstall the bolts. Finally, slide the bash cover back over the lugs, replace the bolts, and put the crank arm back on.
Phase 5: Display Connections
- Connect the Chip to the Display: Up at the top tube, unplug the connector with the red ring from the display. Take the red and black connectors from the PearTune chip and connect them where the original plug was. Important: Match up the arrows on the connectors perfectly.
- Stow the Cables: Carefully feed the chip and any excess wiring down into the down tube.
- Final Step: Screw the display back into the frame.
This installation is a bit complicated, but taking it step-by-step makes it totally manageable to do yourself. Watch the full walkthrough below to see exactly how it’s done!